Forensics

Cannabis Toxicology Project

Throughout history, marijuana has been used as a pain reliever and anxiety reducer. After illegalization, the medical field stopped prescribing marijuana as medication and the stigma against the drug significantly slowed research into its effects. Only recently has the research into marijuana as a recreational and medicinal substance increased, thereby improving our knowledge of the true effects of the active compounds in marijuana. Medically speaking, marijuana is known to help reduce the severity and the frequency of seizures in children, although it is still unknown exactly what substance within the plant is responsible. Currently, patients consume marijuana as edibles. The concentration of active compounds within the edibles widely varies and there has been no record of overdosing on marijuana. However, the long-term effects of marijuana on the developing brain are thought to be detrimental. Like all pharmaceuticals, it is important that the dosage is consistent.

The Dorman lab investigates the variance in cannabinoid concentration upon extraction from marijuana. The variance of each sample is tested using gas chromatography with flame ionization detection. The Dorman lab also investigates pesticide residues and terpene patterns for fingerprinting and source identification. A variety of analytical techniques are employed including headspace analysis, multidimensional gas chromatography, electron capture detection, and mass spectrometry.

Synthetic Drugs Project

A growing problem in today’s society is the use of synthetic drugs as an alternative to their illegal forms. Synthetic drugs appeared in the United States around 2009 with their use being popular among teenagers ages 12 to 17. These drugs are easily accessible and can be found online, in convenience stores, and in head shops. Retailers are not having much difficulty selling these drugs because they label the drugs as “not for human consumption,” and so are technically not breaking any laws. To prevent the abuse of synthetic drugs, many states have passed laws banning them and the Drug Enforcement Agency (DEA) has begun scheduling them. In 2011, the Attorney General started using his power to temporarily schedule drugs such as synthetic cannabinoids and synthetic stimulants. However, as soon as one of the synthetic drugs is scheduled, “street chemists” modify the structure so that the new compound does not fall under DEA regulations. This causes a problem for crime and clinical laboratories when they are trying to identify and analyze these evolving drugs.

The Dorman lab has developed methods for analyzing synthetic drugs, such as synthetic cathinones, synthetic piperazines, synthetic phenethylamines, and synthetic cannabinoids. These synthetic drugs have been analyzed using high performance liquid chromatography and gas chromatography coupled to a mass selective detector, a nitrogen phosphorus detector, or a flame ionization detector, as well as direct sample analysis techniques. However, crime laboratories need one method to analyze these drugs in an efficient manner. The goal of this project is to develop a single analytical method to identify and quantify different classes of synthetic drugs using an instrument found in most crime laboratories. A GC/MS/FID was chosen for this reason, and because the GC-MS can identify the drugs while the GC-FID can quantify them.

Blood Alcohol Concentration Project

Determination of blood alcohol concentration (BAC) is one of the most common analyses performed within forensic laboratories. The protocols for this analysis are often determined by what has been done historically or by instrument manufacturers. This analysis most commonly utilizes headspace sampling, followed by gas chromatography combined with flame ionization detection (GC-FID). Identifications using flame ionization detectors are confirmed by retention time comparison to analytical standards.

The Dorman Lab focuses on method development for BAC analysis, with the goals of improving efficiency, costs, and robustness of the analysis. Amongst the many instrumental parameters, helium has historically been the chosen carrier gas, largely based on convenience and the potential safety issues associated with alternatives, such as hydrogen. According to the Van Deemter Equation, hydrogen has proven to reduce analysis times due to its high diffusivity and high optimal linear velocity. A potential issue due to the emerging helium shortage and increasing cost, has led to the evaluation of using hydrogen supplied through a generator system for the application of this routine analysis. The Dorman Lab also focuses on improving the analysis to include mass spectral data for absolute confirmation in addition to retention time identification. This is done by splitting the column flow to a flame ionization detector for quantification and to a mass spectrometer for identification.

Fingerprint FAME Composition Project

In 2009 the National Academy of Sciences published a report that analyzed the different areas of forensic science and how they could be strengthened. Friction ridge analysis has been investigated since the time of Sir Arthur Conan Doyle, but has come under scrutiny for being a more subjective form of analysis, depending on what the analyst interprets from the ridges as to whether a match between a known and unknown exists. DNA analysis from fingerprints has become possible in recent years, but this might only be useful if the DNA from a print is located within a database and can be referenced. Analyzing the chemical composition of the fingerprint could potentially give information regarding gender and ethnic background of the individual who left it, a possible starting point for investigators in criminal and missing person cases.

The Dorman lab has experience with the chemical characterization of fingerprints. Chemical fingerprint analyses are performed by extraction followed by gas chromatography-mass spectrometry. The ratios of fatty acid methyl esters provided information towards subject’s gender and ethnicity. The Dorman lab also has the ability to analyze these samples via comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry. The ultimate goal of this project is to determine whether gender and ethnic background play a role in the ratios of fatty acid methyl esters found in fingerprints and establish a statistically significant difference in the ratios that can be analyzed in a forensic science to gain subject information during crime scene investigations.